Linked Life Data

1324724

Source:http://linkedlifedata.com/resource/pubmed/id/1324724

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
1992-9-30
pubmed:abstractText
The synthesis is described of a spin-labeled analog of ATP, 2',3'-O-(1-oxy-2,2,6,6-tetramethyl-4-piperidylidene)adenosine 5'-triphosphate (SL-ATP). The spin-label moiety is attached by two bonds to the ribose ring as a spiroketal and hence has restricted conformational mobility relative to the ribose moiety of ATP. The synthesis proceeds via an acid-catalyzed addition of adenosine 5'-monophosphate to 1-acetoxy-4-methoxy-2,2,6,6-tetramethyl-1,2,5,6-tetrahydropyridine in acetonitrile. The spiroketal product is pyrophosphorylated, and alkaline hydrolysis with concomitant aerial oxidation gives the required product. The spin-labeled moiety probably takes up two rapidly interconverting conformations with respect to the ribose ring on the basis of the 1H NMR spectra of its precursors and related uridine derivatives [Alessi et al. (1991) J. Chem. Soc., Perkin Trans.1,2243-2247]. SL-ATP is a substrate for myosin and actomyosin with similar kinetic parameters to ATP during triphosphatase activity. SL-ATP supports muscle contraction and permits relaxation of permeabilized rabbit skeletal muscle fibers. SL-ADP is a substrate for yeast 3-phosphoglycerate kinase, thus permitting regeneration of SL-ATP from SL-ADP within muscle fibers. Electron paramagnetic resonance (EPR) studies of SL-ADP bound to myosin filaments and to myofibrils show a degree of nanosecond motion independent of that of the protein, which may be due to conformational flexibility of the ribose moiety of ATP bound to myosin's active site. This nanosecond motion is more restricted in myofibrils than in myosin filaments, suggesting that the binding of actin affects the ribose binding site in myosin. EPR studies on SL-ADP bound to rigor cross-bridges in muscle fiber bundles showed the nucleotide to be highly oriented with respect to the fiber axis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8043-54
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Synthesis and properties of a conformationally restricted spin-labeled analog of ATP and its interaction with myosin and skeletal muscle.
pubmed:affiliation
School of Biochemistry, University of Birmingham, Edgbaston, U.K.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't